Much of the film's dialogue was improvised by the actors, particularly scenes between Lynch and Bobby.
In the post credits scene "Sergeant Lynch, do you have anything to say for yourself", the voice of the reporter is actually that of director Matthew Reynolds. During the filming of the arrest scene, Conor O'Neill, in character as Lynch, spat in the direction of the cameraman and this was originally intended to be a blooper. However, in post production, audio was removed from the original take and re-designed to sound as though a reporter had confronted Lynch.
The title was devised before production had even begun, and the plot written to revolve around that name.
The rock song playing during key scenes is 'Coming Alive' by Benji Holmes, from the EP 'Coming Alive or Falling Asleep'
Tom Ford's role as Bobby Angel was originally intended to be a small cameo. However, due to his natural chemistry with lead actor Conor O'Neill, it was decided that Angel's relationship with Lynch be developed and additional scenes filmed.